Exam Calculator

How the exam score calculation works

Your final course grade is a weighted average of your current grade (everything before the exam) and your exam score, split according to the exam's weight. If the exam is worth 30% of your course, your current grade covers the other 70%. Once you know two of the three numbers (current grade, exam weight, target grade), the third, the exam score, can be solved for directly instead of guessed at.

The formula is: required exam score equals your target grade times 100, minus your current grade times the non-exam weight, all divided by the exam weight. You do not need to do that arithmetic by hand: enter the three numbers above and the calculator returns the answer immediately, entirely in your browser (see the privacy policy for exactly what that means for your data).

A worked example

Say you are sitting at an 82% going into the final, the final exam is worth 30% of your course grade, and you want to finish with at least a 90%.

Your current grade covers the other 70% of the course, contributing 82 times 0.70, which is 57.4 points toward your final grade before the exam is even factored in. To reach 90 overall, the exam needs to supply the remaining 32.6 points out of the 30% it is worth, which works out to 32.6 divided by 0.30, or 108.7%. Since no ordinary exam offers a score above 100%, a 90% final grade is not achievable in this scenario unless there is extra credit available, or the calculation is rechecked against the exact weights on the syllabus.

Now suppose the target is a more modest 85% instead. The exam only needs to supply 85 minus 57.4, which is 27.6 points, out of its 30% weight: 27.6 divided by 0.30 is 92%. An 85% target is achievable with a 92% on the final, a realistic number to aim for.

When the required score is impossible or already guaranteed

Two edge cases come up often enough to be worth explaining directly, and this calculator flags both.

The required score is above 100%. As in the first part of the example above, this means your target grade is not reachable through the final exam alone, given your current standing and the exam's weight. It does not necessarily mean the target is impossible if your course has extra credit, a curve, or a drop policy that is not reflected in your current grade, but it does mean a normal exam score will not get you there.

The required score is 0% or negative. This means your current grade already guarantees your target grade or better, regardless of what you score on the final. In practice this shows up for students who are already well ahead of their target grade and mainly want confirmation that a poor exam performance will not drop them below it, which is not quite what this calculator checks (it tells you the minimum needed for the target, not the maximum drop you can absorb).

Working out your final exam weight

The exam weight is the percentage of your total course grade the final exam counts for, as set out in the syllabus, separate from every other category (homework, quizzes, midterms, participation) combined. A syllabus that says "the final exam is worth 25% of your grade" is giving you this number directly. If instead it lists point totals (for example, the final is worth 150 points out of 600 total course points), divide the exam's points by the total: 150 divided by 600 is a 25% weight.

Your "current grade" for this calculator should be your grade in everything else, calculated the same way the final grade calculator works out a weighted average from your other categories. If you have not already worked that out, start there, then bring the resulting percentage back to this page.

What this calculator does not account for

This tool assumes a straightforward two-part split: your current grade at one weight, and the final exam at the remaining weight. A few situations need extra care beyond what a single calculation can capture.

If your course drops your lowest exam or quiz score, or replaces a weaker midterm grade with your final exam score if it is higher, those policies change the actual math and are worth asking your instructor about directly rather than assuming they are automatically included here. Similarly, if you have any remaining assignments due before the final exam that are not yet reflected in your current grade, factor those in first using the final grade calculator, so the current grade you enter here is genuinely complete.